| 摘要 |
<p>A microdiffusion system of oxidising and/or reducing gases in groundwater for contaminated sites reclamation is disclosed. The system does not involve the use of electric power and so it can be applied also in those sites where particular safety precautions are required or where no electric power is available. The application of the system involves an in situ configuration. It is based on a gas diffusion process in groundwater characterised by very high efficiency and significant low flows. Gas is fed as micro bubbles that, through their continuous diffusion in the injection point, allow to reach high dissolved gas concentration in groundwater. In this way the system is able to quickly activate biological and/or chemical degradation process in the aquifer, and thanks to high concentration gradient thus created, it has significant influence radius. The system allows to purify the saturated fraction of ground from contaminated substances by reducing and/or oxidising processes. It has a lot of advantages compared to traditional systems, for example: very low site impact, high use flexibility, absence of stripping of volatile substances, absence of biofouling on gas diffusion surface, no waste production.</p> |
